Add vmu rt1170 board

[SpinFast]

Adds the initial vmu rt1170 board and needed FCB configuration for booting.

Depends on:

• Add additional lpuart1 pins to 1176 iomux imxrt-iomuxc#50
• Add vmu rt1170 fcb imxrt-boot-gen#17

[mciantyre]

Looks like this board should be able to, at least, turn on its LED. Mind adding just enough coverage for the board and the hal_led example? I think this should do it:

# We only care that the VMU board can turn on its LED
- --features=board/vmu-rt1170-cm7 --example=hal_led # Other examples, maybe...

I'm prioritizing a CI build of just the board. If there's other examples that are working, it could be nice to add them, but also OK if that doesn't happen / happens later.

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crates.io should have all dependent crates. Everything else LGTM, but I'm not doing a detailed review to check pinouts / hardware capabilities.

[SpinFast]

Looks like this board should be able to, at least, turn on its LED. Mind adding just enough coverage for the board and the hal_led example? I think this should do it:

# We only care that the VMU board can turn on its LED
- --features=board/vmu-rt1170-cm7 --example=hal_led # Other examples, maybe...

I'm prioritizing a CI build of just the board. If there's other examples that are working, it could be nice to add them, but also OK if that doesn't happen / happens later.

crates.io should have all dependent crates. Everything else LGTM, but I'm not doing a detailed review to check pinouts / hardware capabilities.

Yeah that makes sense, thanks! Most of the pins are tied up to internal things or external connectors. The uart, leds, and swd are easily available though so will try and cover those.